When I first learnt OOPS, I struggled to understand it. I was lucky to work on a project that helped me understand it in more detail and overtime I got better at it.
Have you ever struggled to understand a concept/technology and overtime, through practice, become an expert in it?
When something like this happens, people tend to forget how difficult it was for them and judge others harshly, who are going through similar difficulties. This is a variation of a cognitive bias called the curse of knowledge.
If you are unknowingly doing this or are witnessing this in your team, call it out. Your team will thank you.